I've just installed Mathematica 9.0.1 Student Edition on my Laptop and my Home PC.
On my Laptop, it works just fine. But on my Home PC I get this weird issue of the pop-up command autocomplete window ...

For the command autocompletion, I can simply use Ctrk+K and then use Return or Tab to choose the completion. But when I want to autocomplete the local variables I have input, Ctrk+K works, but both ...

I started using Mathematica 9 on Ubuntu 12.10 and, sometimes, autocomplete doesn't work. The suggestions window shows up for just a fraction of second, and quickly disappears.
Do you have any idea on ...

In this answer Brett Champion describes how one can intercept and modify the suggestions used for auto-completion.
Question: Is it possible to modify the suggestion for the automatic auto-completion ...

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